Abstract
Purpose: :
To analyze and compare the spectral transmittance properties of Balanced salt solution (BSS) Plus (Alcon Laboratories, Fort Worth, Texas) and varying concentrations of BSS Plus and ascorbic acid solution with the spectral transmittance of in vitro porcine vitreous.
Methods: :
The vitreous humor from eight freshly enucleated porcine eyes was dissected and successively collected in a cuvette. A scanning monochromator coupled to a fiber optic illuminator passing through an exit port of an integrating sphere illuminated the cuvette. Multispectral images in the range of 420nm to 700nm were obtained using a CCD camera and the spectral transmittance of each sample was calculated. This measurement process was repeated for BSS Plus and four concentrations of BSS Plus and ascorbic acid solution. The solutions of BSS Plus and ascorbic acid were selected to correspond to 1x, 3x, 6x and 9x normal vitreal physiological concentration of ascorbic acid.
Results: :
Porcine vitreous has 91–92% transmission for violet and blue light (420–500nm) over a path length of 10mm, with maximum transmittance of approximately 99% at 615nm. BSS Plus has uniform spectral transmittance of approximately 99% across the visible spectrum (420nm–700nm). The solutions of BSS Plus and ascorbic acid decreased blue light transmission in a concentration dependent manner, but not by as much as the porcine vitreous.
Conclusions: :
BSS Plus transmits more blue light than the vitreous. Addition of ascorbic acid to BSS Plus attenuates blue light transmission although not to the levels found in in vitro porcine vitreous.
Keywords: vitreoretinal surgery • vitreous substitutes • vitreous